On 18.06.19 г. 21:00 ч., David Sterba wrote:
> Minimum stripe count matches the minimum devices required for a given
> profile. The open coded assignments match the raid_attr table.
> 
> What's changed here is the meaning for RAID5/6. Previously their
> min_stripes would be 1, while newly it's devs_min. This however shold be
> the same as before because it's not possible to create filesystem on
> fewer devices than the raid_attr table allows.
> 
> There's no adjustment regarding the parity stripes (like
> calc_data_stripes does), because we're interested in overall space that
> would fit on the devices.
> 
> Missing devices make no difference for the whole calculation, we have
> the size stored in the structures.

I think the clean up in this function should include more here's list of
things which I think will make it more readable. Something like the
attached diff on top of your patch: